An object of the invention is to provide a stronger and more lightweight cyclist helmet, yet while maintaining optimum head protection capabilities.
In accordance with the object of the invention, there is disclosed a generally open concave bicycle helmet comprising a hard external shell, a shock absorbing insert located radially inwardly of said external shell; said external shell defining a number of fore and aft extending structural arms, each of said structural arms having a fore end and an aft end, said structural arms transversely spaced from one another in transversely successive pairs by transverse inter-spacing gaps, said structural arms merging with an annular edge rim at both said fore end and aft end thereof, said insert having radial passageways in register with said inter-spacing gaps, said inter-spacing gaps and said radial passageways forming air ventilation channels; each of said structural arms being arcuate in cross-section, said arcuate structural arms each forming two side walls circumscribing therebetween a corresponding groove, said insert defining an exposed surface, said structural arm side walls being embedded into selected portions of said insert exposed surface; wherein the radius of curvature of said structural arms is greater than that of said insert exposed surface.
Preferably, said structural arms consist of U-shape arms, said arms side wall being inturned against said insert. Said insert exposed surface could include a number of projecting ridges, said insert ridges engaging into each said groove of corresponding said structural arms, said insert ridges extending radially outwardly beyond said insert exposed surface.
The depth of said arms groove could range between 3 and 38 mm, preferably being about 7 mm; while the total width of each of said structural arms could range between 3 and 38 mm, again preferably being about 7 mm. Preferably, the material forming said structural U-arms is molded polycarbonate plastic material. Said structural U-arms could extend in a generally straight fashion in the fore and aft direction, or alternately in a sinusoidal fashion in the fore and aft direction. Alternately, each of said structural U-arms could converge from said aft end to said fore end thereof. Each one of said inter-spacing gaps could range between 3 and 38 mm.
The invention also relates to a bicycle helmet comprising a generally open concave shock absorbing insert, said insert defining a top exposed surface and an internal face in communication with one another via air circulation passageways extending radially through said insert, a number of rigid reinforcing cross-sectionally U-shape hoops extending across corresponding strip portions of said insert exposed surface, each of said U-shape hoops defining two opposite side legs and a groove between said side legs, said hoops side legs being embedded radially inwardly into corresponding said insert strip portions; wherein the radius of curvature of said hoops is greater than that of said insert exposed surface.
In this case, there may be added ridges, radially outwardly projecting from said insert exposed surface integral thereto, said ridges engaging substantially fully into each said groove of said U-shape hoops and also projecting radially outwardly beyond said insert exposes surface. The depth and total width of said ridges could each ranges between 3 and 38 mm, again being preferably about 7 mm. Said hoops could extend in a direction selected from the following: straight, sinusoidal and arcuate patterns.
The invention also relates to a bicycle helmet comprising a generally open concave shock absorbing insert, said insert defining a top exposed surface and an internal face in communication with one another via air circulation passageways extending radially through said insert, a number of rigid reinforcing cross-sectionally U-shape hoops extending across corresponding fore and aft extending strip portions of said insert exposed surface, each of said U-shape hoops defining two opposite side legs and a groove between said side legs, said hoops side legs being embedded into corresponding said insert strip portions; wherein the radius of curvature of said hoops is greater than that of said insert exposed surface.
This invention relates to protective headgear for use on roads by cyclists.
Protective headgear helmets for use by bicyclists need to address a number of needs, some of which being difficult to reconcile with one another. The first need is of course to provide proper protection of the cyclist head from trauma injury following accidental impacting fall to the ground, notably when the bicycle rolls at high speed on the ground. In particular, the helmet should be so constructed as to be resistant to fragmentation after a first violent impact, as many high speed falls of cyclists involve multiple ground impact of the cyclist head. A helmet is of course of limited value if it is effective in protecting the cyclist head from impact trauma from a first ground impact, but becomes inoperative afterwards due to fracturing, fragmenting or the like impact borne deformation. Helmets also need to provide suitable shielding protection against headborne sun stroke, since it may not be readily apparent to the cyclist that a sun stroke is imminent because of the incoming wind that refreshes his/her face as his bicycle moves forward. Helmets should also preferably provide for proper air ventilation of the head, again to fight against sun strokes. On the other end, the weight of the helmet should be kept down as low as possible, so as not to generate fatigue to the neck of the cyclist, as this would be a safety hazard in compromising the attention span of the cyclist when his vehicle is on the road. Prior art helmets still do not provide for an optimum mix of these desirable parameters.